A Monmouth University poll in April found that 43% of Republicans versus 5% of Democrats do not plan to get vaccinated.

The University of Pennsylvania also recently announced it would require that all employees and clinical staff be vaccinated by Sept. 1. Currently, nearly 70% of the staff are vaccinated, although Brennan said rates among doctors and pharmacists are closer to 90%. 

A key factor in the decision was that the systems’ six hospitals treat quite a few cancer and organ transplant patients as well as elderly patients highly vulnerable to the virus, Brennan said. He believes that hospital workers are more likely than the general public to get vaccinated, but they also share many of the same fears. 

Some of the greatest resistance is political. A Monmouth University poll in April found that 43% of Republicans versus 5% of Democrats do not plan to get vaccinated. Less than half of the GOP caucus members in the House have acknowledged getting vaccinated.  

Sen. Rand Paul, a Republican from Kentucky and an eye doctor, has refused to get the vaccine. Paul, the first known senator to test positive, says he’s already immune.